Method and apparatus for the treatment of gas-permeable and/or liquid-permeable materials



March 31, 1970 H. FLEISSNER 3,503,136

THE TREATMENT OF GAS-PERMEABLE AND/OR LIQUID-PERMEABLE MATERIALS METHOD AND APPARATUS FOR Filed. Dec. 5, 1968 //7 Van/0r. HE/N2 #4429605? 6a? 3 m A b O O O m .V O O O O O O O O Q 8 mm mm United States Patent 3,503,136 METHOD AND APPARATUS FOR THE TREAT- MENT 0F GAS-PERMEABLE AND/ OR LIQUID- PERMEABLE MATERIALS Heinz Fleissner, Egelsbach, near Frankfurt am Main,

' Germany, assignor to VEPA, AG.

Filed Dec. 5, 1968, Ser. No. 781,503 Claims priority, application Germany, Dec. 6, 1967, 1,635,357 Int. Cl. F26b 5/04 US. Cl. 34-15 22 Claims ABSTRACT OF THE DISCLOSURE The present disclosure is directed to a method and apparatus for the treatment of gas-permeable and/or liquidpermeable materials which comprises introducing the material to be treated to a treatment housing, conveying the material on the surface of a perforated conveying element through the treatment housing while penetrating said material with a circulating treatment medium, sensing the pressure on both sides of the material being treated, thereby determining the pressure differential between the inside and outside of the conveying element and accordingly varying the capacity for circulating the treatment medium depending on said pressure differential and the material being treated.

Background of the invention The present invention relates to a method and apparatus for the treatment of gas-permeable and/or liquid-permeable materials, particularly delicate textile materials, utilizing at least one perforated conveying means, for example a sieve drum means subjected at least partially to a suction draft or to an excess pressure. The material to be treated is passed through the treatment chamber which contains a device for the circulation of the treatment medium.

Devices with sieve drums subjected to a suction draft are well known and are used for drying, steaming, heatsetting and thermosoling as well as for curing woven and knitted fabrics and non-Wovens. Also, washing devices with sieve drums subjected to a suction draft are well known. In order to avoid a marking of the drum perforation when delicate materials are treated, the perforated drum jacket is frequently surrounded by a fine gauge wire mesh. Also, devices are known in which the perforated drum is first covered with a wide-meshed wire mesh and then with a fine-gauge wire mesh. By utilizingtwo wire meshes it is attempted to equalize the suction draft over the entire working width of the conveying means.

In well known devices, in order to permit a full utilization of the machine when handling materials with varying permeabilities, the fans are generallyrated for the maximum and/ or most economical capacity.

It has been found to be disadvantageous that not every material can be effectively treated on such devices. For example, when handling delicate materials such as lining fabrics, even a fine-gauge wire mesh might mark the linings during drying. In the case of structural fabrics of texturized polyesters, a flattening of the structure by several times during heat-setting has been experienced. Also, it has repeatedly been found that especially in the highgrade finishing of the textile material with synthetic resins, better results have been obtained on a one drum dryer than on a device containing several sieve drums.

For many applications and especially for commission finishers, the devices should be versatile and equally suited for any material type and treatment process regardless of the varying requirements.

3,503,136 Patented Mar. 31, 1970 Summary of the invention An object of the present invention is to avoid the prior art disadvantages in the treatment of gas-permeable and/ or liquid-permeable materials.

Another object of the present invention is to provide an improved process and apparatus for the treatment of gaspermeable and/or liquid-permeable materials wherein a variety of different materials of varying delicacy can be effectively treated in the same apparatus.

A further object of the present invention is to provide an improved process and apparatus for the treatment of gas-permeable and/or liquid-permeable materials wherein delicate materials, such as for example lining fabrics, can be effectively treated without marking the lining during drying.

Still another object of the present invention is to provide an improved process and apparatus for the treatment of gas-permeable and/or liquid-permeable materials wherein structural fabrics of texturized polyesters can be effectively treated without flattening the structure of the material as experienced in the prior art processes and apparatus.

Other objects and further scope of applicability of the present invention will be apparent from the detailed description given hereinafter; it should be understood, however, that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.

Essential for the present invention is the knowledge that the prior art disadvantages are generally due to the result of the power of the suction draft utilized, that is the differential pressure between the drum interior and the space outside the drum. Thus, for example, if delicate materials are involved, better results can be obtained when using a weaker suction draft.

Pursuant to the present invention, it has been found that the above-mentioned disadvantages may be eliminated and a much improved process and apparatus for the treatment of gas-permeable and/or liquid-permeable materials may be obtained by designing the device for circulating the treatment medium in such a way that its capacity can be varied depending upon the pressure difference between the inside and outside of the conveying element. This can be achieved in an effective way by connecting an infinitely variable gear, for example between the fan drive and the fan in a dryer and for example, between the pump drive and the pump in a washing device. This gear may be set by hand or by means of a servomotor. However, instead of such a gear, a commutator motor can be also used which is set to the respective speed of the process involved.

According to the permeability of the material to be processed, the partial vacuum and the conveying elements, for example sieve drums, and/or the pressure difference between the drum interior and the space outside the drum varies at a constant fan speed. In the well known devices and in the case of materials which are well permeable to air, this pressure difference may, for example, be in the range of about 30 to 40 mm. water column, whereas it may increase to about 60 to mm. water column if denser materials are handled which are only slightly permeable to air. Furthermore, it has been found that in a drying process materials become more permeable to air with progressive drying, and that therefore, in a device with several sieve drums, the pressure difference between the interior and exterior of the drum decreases gradually from drum to drum. Conditions may be reversed in a washing device. Thus, due to the swelling of the fibers, the fabric may become continually less permeable to the liquid. Accordingly, the differential pressure to be overcome at the same pump speed increases.

1111 order to ensure the exact reproduction of several chemical and/or textile technological processes in continuous operation, it is necessary to provide constant treatment conditions. As mentioned, constant conditions could not be achieved in the devices used up to now due the the varying pressure differences.

-In accordance with the present invention, and to eliminate these deficiencies it is suggested to correlate to each sieve drum a device which indicates and/ or measures the differential pressure between the drum interior and the space outside the sieve drum. The fan speeds can then be adapted and changed to achieve the respective and/or the desired differential pressure.

In continuous operation, that is if the devices are used as part of a continuous process line, it is frequently more advantageous, according to the present invention, to couple the measuring unit with a control device for the fan drive or the pump drive, so that a predetermined differential pressure is kept constant regardless of the respective processing material and its permeability. By means of this control unit and by means of the measuring unit, the differential pressure can be adapted to the respective optimum processing conditions.

The well known devices with sieve drums subjected to a suction draft have a stationary axis to which the battle which interrupts the suction draft at that drum portion which is not covered wtih the material being treated is fastened. For these devices and in a further embodiment of the present invention, it is suggested to bore the stationary axis, preferably up to the plane which substantially halves the working width of the drum and to connect one side of the differential pressure measuring unit, for example an U-tube filled with liquid, to this boring. The other side of the measuring unit is connected to a pipe which is arranged outside the drum near the drum jacket and which preferably also extends up to the plane which substantially halves the working width of the drum. It is advantageous if, according to the present invention, a pipe is mounted to the stationary bored drum axis, preferably vertical to this axis, said pipe being connected With the boring of the drum axis and extending in close proximity to the drum jacket at the drum side which is covered with the material being treated. In this way, it is ensured that the differential pressure which is exerted directly on the processing material can be clearly determined.

The measurement of the differential pressure can be effected in the same way with a device with blower drums. In these devices an excess pressure prevails in the drum and a normal pressure outside the drum.

Brief description of the drawings The present invention will become more fully understood from the detailed description given hereinbelow and the accompanying drawings which are given by way of illustration only and thus are not limitative of the present invention and wherein:

FIGURE 1 is a longitudinal section of the apparatus of the present invention;

FIGURE 2 is a cross section of the apparatus of the present invention according to FIGURE 1;

FIGURE 3 is a measuring unit for determining the differential pressure existing between the inside and outside of the sieve drum means;

FIGURE 4 shows a regulating device for automatically controlling the suction draft or positive pressure; and

FIGURE 5 illustrates a rotary manometer used for indicating the pressure differential between the inside and outside of the conveying means.

Brief description of the preferred embodiments Referring now to the drawings, wherein like reference numerals are used throughout the various views to designate like parts, the apparatus of the present invention according to FIGURES 1 and 2 comprises a heat-insulated housing 1 which is subdivided by a partition 2 into a treatment chamber 3 with sieve drums 4 subjected to a suction draft and into a fan chamber 5 with fan wheels 6 which are correlated to the faces of the sieve drums 4. The fan chamber also contains heater batteries. Above and beneath the sieve drums 4 perforated sheets 8 are arranged for equalizing the airflow.

A fan drive 9 is provided with an infinitely variable gear 10 which, in the embodiment of the present invention as shown, can be varied by means of a handwheel 11. However, in general it is more expedient to operate the gear from the control desk via a servomotor.

In each sieve drum a stationary drum axis 12 is arranged which supports a baffle 13. In the embodiment of the present invention shown the drum axis 12 is bored and provided with a pipe 14 which is connected with a boring 15 of the drum axis. Outside the sieve drums 4 at the sides which are covered with the material being treated, another pipe 16 is arranged. The pipe 16 as Well as the bored drum axis 12 are connected with a U-tube 17 which is filled with liquid and which is arranged at the outer face wall of the housing 1. The differential pres sure can be read from a dial 18 which is correlated to the U-tube. Instead of the U-tube, a rotary manometer (pressure gauge) 29 or a similar indicating instrument may also be used. When using a roatary manometer 29, the pressure difference is indicated on scale 18 by means of a pointer 30. The infinitely variable gear 10 is connected with the intermediate connecting gear 33 and servomotor 32. A line 31 connects the servomotor 32 with the potential generator 28, said generator being connected to a pressure gauge device 29. Accordingly, the measuring device as well as the indicator device are coupled with the control device for regulating the suction draft or positive pressure. The drum drive is effected by means of a gear 20 via a hollow shaft 19.

At the inlet of the apparatus shown a creel 21, rollers 22 and a tensioning roller 23 are arranged. Behind the creel 21, material guides 25 are provided for a material 24 to be processed. In order to permit a tensionless feeding or an overfeeding of the material onto the sieve drums 4, a driven pair of rollers 26 is arranged at the inlet of the apparatus. At the discharge end of the apparatus a cooling drum 29 is provided. The alternate arrangement of the baffles 13 as shown permits the automatic threading of the material and its passage from drum to drum when the device is started up.

The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be apparent to on skilled in the art are intended to be included within the scope of the following claims.

It is claimed:

1. An apparatus for the treatment of gas-permeable and liquid-permeable materials which comprises a treatment housing, means for introducing the material to be treated to the treatment housing, at least one perforated conveying means rotatably disposed with said housing, circulating means provided with a drive means and as sociated with the conveying means for at least partially subjecting said conveying means to a suction draft or a positive pressure, means associated with said drive means for varying the speed of rotation of the circulating means, thereby varying the capacity for circulating the treatment medium, and means for removing the material being treated from the treatment housing.

2. The apparatus of claim 1, wherein the circulating means is a pump means.

3. The apparatus of claim 1, wherein the circulating means is a fan means.

4. The apparatus of claim 1, wherein means are provided in the interior of the conveying means and in the conveying means and the space on the outside of the space on the outside of the conveying means for measuring the differential pressure between the interior of the conveying means.

5. The apparatus of claim 4, wherein the measuring means communicates with a control unit for the drive of the circulating means for controlling the suction draft or the positive pressure, depending on the differential pressure measured between the inside and the outside of the conveying means.

6. The apparatus of claim 1, wherein the means for varying the capacity for circulating the treatment medium is an infinitely variable gear means.

7. The apparatus of claim 6, wherein the gear means contains a handwheel for mechanically varying the capacity of the circulating means.

8. The apparatus of claim 5, wherein the control unit is a servomotor.

9. An apparatus for the treatment of gas-permeable and liquid-permeable materials which comprises a treatment housing, inlet means for introducing the material to be treated to the treatment housing, at least one sieve drum means rotatably disposed within said housing about a drum axis, a portion of said drum axis being bored out and communicating with a first pipe means which senses the pressure on the inside of the sieve drum, second pipe means disposed in the treatment chamber on the outside of the sieve drum and near the material being conveyed thereon, said second pipe means communicating with the bored out portion of the drum axis, indicator means associated with said pipe means for measuring the differential pressure between the inside and outside of the sieve drum, circulating means containing a drive means and associated with the sieve drum means for at least partially subjecting it to a suction draft or a positive pressure, means associated with said drive means for varying the capacity for circulating the treatment medium, and outlet means for removing the material being treated from the treatment housing.

10. The apparatus of claim 9, wherein the first pipe means communicates with the bored out portion of the sieve drum axis at about the center of the sieve drum and extends substantially perpendicular to said axis, terminating near the inside surface of the sieve drum means.

11. The apparatus of claim 10, w erein the second pipe means extends into the treatment chamber to about the middle of the sieve drum means and substantially parallel to the outer surface of said sieve drum and in close proximity thereto.

12. The apparatus of claim 11, wherein the first tube terminates at the inside surface of the sieve drum in close proximity to where the second tube terminates at the outside surface of the sieve drum.

13. The apparatus of claim 9, wherein the indicator means is a U-tube filled with a liquid, and the differential pressure is read from a dial which is associated with said U-tube.

14. The apparatus of claim 9, wherein the indicator means is a rotary manometer.

15. The apparatus of claim 9, wherein the indicator means communicates with a control unit for the drive of the circulating means for controlling the suction draft or the positive pressure, depending on the differential pressure measured between the inside and outside of the sieve drum means.

16. The apparatus of claim 9, wherein the means for varying the capacity for circulating the treatment medium is an infinitely variable gear means.

17. The apparatus of claim 9, wherein the gear means contains a handwheel for mechanically varying the capacity of the circulating means.

18. The apparatus of claim 9, wherein the inlet means is a creel containing a plurality of rollers including a tensioning roller.

19. The apparatus of claim 9, wherein the outlet means is a cooling drum.

20. A method for the treatment of gas-permeable or liquid-permeable materials which comprises introducing the material to be treated to a treatment housing, conveying the material on the surface of a perforated conveying element through the treatment housing while penetrating said material with a circulating treatment medium, sensing the pressure on both sides of the material being treated, thereby determining the pressure differential between the inside and outside of the conveying element, and varying the capacity for circulating the treatment medium depending on said pressure differential and the material being treated.

21. The method of claim 20, wherein the capacity for circulating the treatment medium is varied manually.

22. The method of claim 20, wherein the capacity for circulating the treatment medium is varied automatically in response to the measured pressure differential.

References Cited UNITED STATES PATENTS 2,919,496 1/1960 Fleissner 34-115 3,081,556 3/1963 Fleissner 34-115 3,140,157 7/1964 Fleissner 34-115 3,303,576 2/1967 Sisson 34-15 FOREIGN PATENTS 484,074 10/ 1929 Germany.

WILLIAM J. WYE, Primary Examiner US. Cl. X.R. 34-52, 115, 122 

